It is called the Ikea effect

You usually come out with more than you originally bargained for. Or, the two-meter sofa suddenly looks much larger than it did inside. This can pose a significant problem when you suddenly realize that your own transport is inadequate. In order to avoid this kind of situation, we rely on our own logistics and transport department to coordinate equipment delivery, directly to the venue. This is not an effect; it is simply part of the service.